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    <meta charset="UTF-8">
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    <title>Document</title>
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<body>
    <script>
        var str = '这是字符串';
        console.log(typeof str);
        var num = 20;
        console.log(typeof num);
        var bool = true;
        console.log(typeof bool);
        var a;
        console.log(typeof a);
        var b = null;
        console.log(typeof b);
        var obj = {
            name:'老周',
            sayHi:function(){
                console.log('hi');
            }
        }
        console.log(typeof obj);
        obj.sayHi();
        var arr = [1,2,3];
        console.log(typeof arr);
        var date = new Date();
        console.log(typeof date);
        var fun = function(){}
        console.log(typeof fun);
        var str1 = str.substr(1);
        console.log(str1);
        
    </script>
</body>
</html>